osmo learning system

, item: "Medium box", Qty:30 } ], "majority", wtimeout:100 } ); } Catch (e) { print (e); } Return value: If The primary and at least one secondary acknowledge each write operation within { true, "Insertedids" : [ ObjectId ("562a94d381cb9f1cd6eb0e1a") ), ObjectId ("562a94d381cb9f1cd6eb0e1b"), ObjectId ("562a94d381cb9f1cd6eb0e1c") ] } Timeout returned: Writeconcernerror ({ "code": +, "Errinfo" : { "wtimeout": true }, "ErrMsg"

1:unix file Type-3 typesNormal files (regular files): Text files (plain text, scripts, source programs, configuration files, HTML, etc.), binary files (multimedia files, databases, etc.)Directories: for organizing filesPseudo-file: does not store data for the purpose of providing a service. Divided into three kinds:Special files: Device drivers, file representations of physical devices (keyboards, monitors, etc.)Named pipes: Directing the output of one program to the input of another programProc

逻辑卷lv0的快照lv0-backupmount /dev/vg0/lv0-backup /mnt ##挂载The size of the snapshot determines the size of the operation space, and when the write content is larger than the snapshot size, the snap is corrupted.rm -fr /mnt/* ##修改数据（假设误操作删除了设备所有文件）Reset:umont /mnt ##卸载快照 lvremove /dev/vg0/lv0-backup ##删除损坏的快照文件lvcreate -L 40M -n lv0-backup -s /dev/vg0/lv0 ##重新创建快照lv0-backupmount /dev/vg0/lv0-baackup /mnt ##重新挂载快照4. Removal of Logical Volume LVM(1)先删除快照：lvremove /dev/vg0/lv0-kuaizh

status, listening portnetstat -lnp-l lists only the service states that are in Listen (listening)-N refuses to display aliases, showing all numbers converted to numbers-P Displays the program name that establishes the associated linkNETSTAT-LNP |grep + port number or service nameYou can see if a service is started, or you can view the process with PSnetstat -ltnpView Only TCPnetstat -lunpView Only UDPNetstat-an List all port statesIf the server you are administering is a server that provides We

that a machine can directly connect to the B machine's 22 port.Take my own environment for example, a machine for windos host, IP for 192.168.226.1b Machine for VMware inside LINUX1, there are two network cards, ENS33 IP for 192.168.226.129ENS37 to 192.168.100.1C Machine for virtual machine linux2, IP for 192.168.100.100Now how to configure can let the host SSH connection linux2?1. Route forwarding is still turned onecho "1" >/proc/sys/net/ipv4/ip_forward2 Configuring routing RulesA on the exec

Let's review the previous section:1. Set Password command passwd2. User Information Modification Command usermod3. User Delete command Userdel4. Job: Modify User1 User ID 505, home directory to admin, user Group is admin, finally delete user1 userUsermod–u 505–d/home/admin–g Admin User1Userdel user1In this section, we continue to talk about user management-related commands1. Add User group GroupaddThe use of this command is simple groupadd groupnameAfter the addition is complete, you can view th

device to which the system is to be joined. (i = major% 255), and then adds a node object of type struct probe to the linked list managed by Probes[i], as shown in 2-6. The darker part of the rectangular block in which the struct probe is located is what we focus on, and the information about the character device object currently being added to the system is recorded. Where Dev is its device number, range

Job ListLinux kernel Analytics Job: Analyze the assembly code to understand how a computer works with a simple C program: How the Linux kernel analyzes the job, how the operating system works: Complete a simple time slice rotation multi-channel program kernel codeLinux kernel Analysis Job 3: Trace analysis of the boot process of the Linux kernel Linux kernel analysis job 4: Using the same system to call the

4.2 "Linux learning is not difficult" get Linux system Help (2): Use the man manual pageAfter installing the Linux system, the first thing to do is to learn how to get help under Linux, Man manual page is a good way, man is a command to display the Unix/linux online manual. Can be used to view a command, function, or file's Help manual, and it can also display so

Free Learning for smart car system solutions This design scheme is dedicated to all the riders who fought alone like me. May you take a detour. This quad-rotor solution may be the simplest and most feasible solution, mainly based on the size of the light source to distinguish between front and rear lights and beacon. It is intended to serve as a reference and hope that the great gods can put forward sugges

In the trance between the landlord has been sophomore, this time period I am afraid not to think about what to start looking for work and other things, honestly learn something is the most important, so I aimed at the operating system of learning, nachos is a learning operating system, easy to get started, and UC Berke

The my records integrated system developed based on the wojilu framework is worth studying. The following are the learning suggestions of wojilu authors. Bytes ---------------------------------------------------------------------------------------------------------------------------- [Learning suggestion]For a better learn